ALU-PREP -A. – Metal Cleaner for Aluminium
Aluminium being an Amphoteric Metal needs a different system of cleaners. This cleaner is formulated to meet this requirement. It is a non-silicate metal cleaner. Basically, it is a Hot-Soak Cleaner, but it can as well be used for cathodic cleaning. This is a highly efficient and a long life cleaner. It is to be used for Aluminium and its Alloys, prior to electropolishing, electroplating and anodising. It produces a slight etch on the metal surface. If more etch is desired, it can be used with an addition of sodium-hydroxide (5 to 7 g/l). It removes polishing compose, drawing and pressing oils etc.
EQUIPMENT
Welded steel tank with M.S. Heaters and fume extractor.
PROCEDURE
| Alu-prep-A | 30-40 g/l |
|---|---|
| Fill in the tank with water to about 2/3 its capacity. To it, add, with stirring, the cleaner. Stir till it dissolves. Make up to volume after dissolution. No need to heat the water, for dissolution of the cleaner. | |
A) SOAK CLEANING
- Heat the solution to 60°- 70°C’
- Immersion time can be up to ~ minutes depending upon the condition of the articles
B) CATHODIC CLEANING
- For cathodic cleaning heat the cleaner solution to 60°-70°C
- Current density – 10-20 Amps./sq. ft.
- Cathodic cleaning time can be from 1/2 to 2 minutes depending upon the state of the article.
Articles cleaned by soak cleaning or cathodic cleaning are to be sealed well before they go in for further processing.
MAINTENANCE
Cleaner salts be added to the solution from time to time to maintain the alkalinity at its original value.
NOTE
Time and Temperature can be varied as per the requirements depending upon the type of alloys, the etch required, the rate of the articles etc.
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